Crucible-furnace.



E. H. SCHWARTZ. ORUGIBLE FURNACE.

' APPLICATIONFILED:$EPT.21.1908. Patented Feb 2,

3 SHEETS=-BHEET 1.

E. H. SCHWARTZ. 1 GRUUIBLE FURNACE.

. APPLICATION FILED SEPT. 21. I908. 9,1 1,271. V Patented Feb. 2, 1909.

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ig Zia QMW, @W W B. H. SCHWARTZ. GRUGIBLE PURNAGE. PPPPPPPPPPPPPPPPPP PT.21,'1908. 91 1,271. Patented Feb. .2, 1909. I v 3 EEEEEEEEEEEE 3.

UNITED STATES PAT onricn.

EDWARD H. SCHWARTZ, OF CHICAGO, ILLINOISLASSIGNOR 'ro KROESCHELL- BROTHER COMPANY, OF. CHIOAGQ ILLIKOIS, A CORPORATION OF ILLINOIS.

annotate-summon- Application iiledseptember 21, 190 Serial No.463,900.

To all it may. concern."

Be it known that I, EDWARD H. SCHWARTZ, a citizen of the United States', residingiat Chicago, in the county of Cook; and State'of Illinois, have inventeda new and useful Im-. provement in Crucible-Furnaces, of which the following is'a specification. v

My invention relates to an improvement in the class of crucibleefurnaces. in which the fuel (gas or oil) and the airfor promotingble to cause its contents to melt from the bottom upwardly, with the advanta e of'.em-' rom the ploying the heat of conduction lower molten portioffpf. the mass to the upper solid portion. thereof to expedite the melting operation, which, is an important consideration in melting nietals with'but slight oxidation of the metalswhile melt ingthem; whereby the. heat of combustion shall be distributed unifor'mlyiabout the crucible in its gyratorily-ascending course through the furnace-chamber, and whereby,

other advantages shallbeattained to the end of enhancing the efticiencyof the furnace.

In the accompanying, drawings, Figure -1 is a view in front elevation of my improved furnace shown as a tilting furnace; Flg. 2.

his a top plan view of the same; Fig. 3 is a section on line 3, Fig. 2, and Fig. 4, a section on line 4, Fig. 3; Fig. 5 is a section on line 5, Fig. 1, with a dotted-line representation of the furnace, in its tilted Fig. -7 is av section taken at their-regular "line 7 on 3. n The cylindrical metal casing 8' contains in' its base-portion a metal sill .9. formed of similar upwardly. diverging end-sections 10,.

longitudinally.channeled and provided with lateral flanges 11" at"whi'ch-; the diverglng-"seo tions are secured to the inner; surface of the I casing at diametricallyopposite 'parts there of"; andtheieeendlseetionsare connectedby'a' I Specification of Letters Patent.

osition; Fig. 6 is. a; plan view on line 6, Fig. 1, showing the". furnace with its hinged cover removed, and

Patented Feb. 2, 1909.

base-section ,12 extending parallel with the I bottom. of the casing'to produce. therewith an interpo sed air-channel-forming space 13 communicating at its e ds with upwardly I tapering extensions l4, 14,formed by. the endsections 10 and adjacentqportions of these casing-surface.

The-casing contains asuitable refractory lining 15 forming a raised base .16 form'ed with a circular concave crucible-seat 17, .of

arc-shape in cross section .for the purpose as hereinafter explained, from which the upper surface of the refractory base slopes, as shown, to form, a species of annular gutter 18 having a slag-discharge outlet l9textending from it throughthe lining-baseto a hit] ged :door 20 hung onthe lower part of the casing to cover an openin therein flankedby, downwardly flaring] anges 21 I connected at their wider ends by a. horizon-.

tal flange 22 to form an inclined seat for the door and cause it to open by gravity and ,fha'ng. vertically when the. furnace is tilted,

as hereinafter described. The furnacecover 24, hinged at .23, is releasably fastened ata lug'25 projecti'ng'from its edge opposite the hinge by. parallel links 26 adapted to embrace, the lug; and carrying between-their. free ends a cam 27 provided 1 with a handle28 by which to manipulate it for engaging the camwith and disengaging it fromthe lug to lock and unlock the cover. This cover, like the body of the furnace, is formed of a metal exterior with a refractory lining 29; and it' contains a central charging-opening 30 for closing which a 90.

supplemental lined cover 1241 is provided, hinged at 123 and containing' ,a central opening 130 forming anout-let for the spent ases. The crucible 31, which is shown of ongit-udinally-bowed shape, is formed with a convex bottom 131 conforming to the seat 17 toadaptitv to, fit stably therein, thus without tendency-t0 shift, two removable confining bricks 117 being fitted at suitable intervals about its open end tohold it in place in tilting the furnace; and the crucible 15 equipped with a pouring-spout .2'3l,registering with and conforming. to aiprotuber ance 8 8onf the furnac'body". t adapt the furnaceto be tilted for pouring, it is supported on .tr unnions 32, 33 in bearings 34 on thenpper ends: of standards" The hollow trunn1on. 3'3, which islonger e 49 abo t the head of the nozzle.

'. ported tc 55 feed-valve than the trunnion 32 and closed at its outer and, carries, for tllting the furnace, a worm-,

wheel 36 engaged by a Worm 37 on a shaft 38 journaled in a bearing 39 on one of the 5' standards 35, the worm-shaft carrying a miter-gear 40 with which meshes a miter- -pinion 41 on a shaft 42 carrying a hand- .wheel 43. v

Along the standard 35 which carries the trunnion-bearing 34 extends a vertical airpipe 44 communicating with a blower (not shown) at an inlet 45 near its lower end and opening at "its upper end into the trunnion Where'the screw-plug 46 which closes its 1 5 outer end forms avalve for regulating the supply of air from the pipe 44 into the trunnion, from. the innerend portion of v which the air-passage is continued by a depending pipe 47 constricted toward its lower .20 flanged end, where it meets and issecured to the casing 8 to register with an air-inlet opening48 therein at the upper part of a channelextension 14. From the channelextensions 14, near their upper ends, airducts .114 and 214 extend diagonally to af ford open communication through thembetween the channel-sections and furnacechar .er at the gutter 18. Between its ends the pipe 47 opens into a branch 147 extending at right-angle from it and discharging into a mixing-chamber 49 for the fuel and air, secured to a lined-metal protuberance 50 on the casing 8 to one side" of the duct 114 and containing an inwardly-flaring fuel- 35 inlet port 51, one side of which is tangential to the inner wall of the furnace-chamber. The chamber 49, which is open at its outer end and is provided in its inner end With a discharge-opening 149 registering with the aon-eceiving-end of the port 51, contains a nozale 52 of peculiar construction. The outer end of the nozzle is a funnel 152 closing the corresponding end of, the chamber 49 and terminating at the discharge-end of the 4'5 branch 14? in a circumferentially corrufor heat, a pipe 54 funnel-'fori'nir to cover 124 is raised for charging into the cruv cible through the cover-opening 30 the metal to be melted. Thus the cover 24 need never be opened except for introduc ng and removing a crucible and for repairing purposes,

as so that the furnace remainsclosed whlle in a furnace of the type shown. and

operation and also While pouring, with the advantage of thereby avoiding impairment of its heat. With the valve 55 then opened and the fuel ignited, the fuel is drawn through the nozzel 52, (drawing air with it through the funnel 152), by the vacuum produced in the nozzle by the air under pressure passing through the ducts 352 and space 53 from the branch-pipe 147 for mixture with the gaseous or vaporized nel wherein it affords astored supply for feeding the farm" through the diagonal ducts. The ga their course from the port 51, encoun 2r the forcibly entering their path in .ne same (infection through the "ducts 114 and 214 and alfording the additional quantity of air to complete combustion of the unconsumed gases, whereby the greatest intensity of the heat is generated at the'base of the crucible to exert the bottommelting function referred to upon its contents, and the heat of the gyrating from that point is rendered uniform in its distribution about the crucible.

To attain in the manner described the advantage of melting from the bottom of the crucible upwardly,'it is not necessary that the furnace shall be tilting, for the same result may oe attained in a simihe manner in described in Letters Patent No. 892,012, mind to me June 30, 1908. However, the tilting function of the furnace is advantageous in facilitating the pouring and permitting loss of heat to be avoided in the operation, and,v moreover, when, in tilting, by turning the hand-wheel 36, the flap-door 520 opens, slag in the bottom of the furnace-cb mber, from which the slagoutlet 19 lead to the dooropening, will be subjected to portion of the ame that will 1 through that outlet may hav flow and Vi hat l i e! aim as new,

and (.hIiz-lliki to secure by Letters Patent, is-

1. In a crucible-furnace, an inlet-port for burning gases leading tangentially into the base of the furnace-chamber through its well, and operating to circulate the hot gases gyratorily about the crucible, and an airduct leading inclinedly through said wall into said base to dischargeinto the path therein of said gases, for the purpose set forth.

J 2. In a crucible-furnace,a concave crucible-seat of arc-shape in cross-section in the base of the furnace-chamber with a gutter surrounding said seat and a slag-discharge outlet leading' from the gutter through the furnace-wall, a door, for closing said'outlet, an mlet-port for burning gases. leading tangenti'allyinto said gutter through the furnace-wall, and an air-duct leading diagonally through said wall into said gutter, for the purpose set forth. p

3. In a crucible-furnace, an inlet-port for burnin gases leading tangentially into the base 0 the furnace chamber throughits wall, and operating to circulate the hot gases gyratorily about the crucible, airducts leading through said wall into said base to discharge into the path therein of .said gases, and an air-channel connecting said ducts across the bottom of the "furnace,

' for the purpose set forth.

4. In a crucibleiurnace, an inlet port for burning gases leading tangentially into the base of the furnace-chamber through its Wall, air-ducts leadinginclinedly through saidwall into said base to discharge into an the path therein of said gases, andan 3 5.1? channel connecting said ducts, comprising upwardly extending end-sections and an intermediate section extending across the bottom of the furnace, for the purpose set forth.

5. In a crucible furnace, an inletport'ifor' V burning gasesleading tangentially into the base of the furnace-chamber through its wall, an air-duct leading through said wall intO said base to discharge into the path therein of said ga'ses, a'n alr-supply conduit communicating with said duct, a mixingchamber communicating with said inletport and containing a nozzle, a branch-pipe connecting said conduit and mixing-chamber, and a feed-valve discharging into the mixing-chamber, for the purpose set forth.

' 6. In a crucible-furnace, an inlet-port for burning gases leading tangentially into-the base of the furnacewchamber throu h its wall, an air-duct leading through sai wall into said ,base to discharge into the path therein of} said gases, an'air-supply conduit communicating with saidv duct, a mixing-- chamber communicating with said inletport and containing a nozzle having a head iprovided with air-ducts leading-obliquely to its tubular interior, and a feed-valve discharging into the .niixing-chamber, for the purpose set forth.

. 7, In a crucible-furnace, an inletort for I burning gases leading tangentially into the base of the furnace-chamber through its Wall, air-ducts leading inclinedly through said wall into said base to discharge into the path therein of said gases, an air-channel connecting said ducts, an air-sup ly conduit EDWARD 1-1.- SCHWARTZ. In presence of' K. M. CORNWALL, R. 'A, SCHAFER. 

